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Primary amoebic meningoencephalitis is an acute disease of the central nervous system of humans and animals caused by Naegleria fowleri. This report describes a case of meningoencephalitis caused by N. fowleri in a crossbred, one-year-old bovine with progressive neurological signs. At necropsy there was thickening of the meninges and multifocal areas of malacia in the thalamus, caudal and rostral colliculi, parietal and occipital cortex, and cerebellum. Histologically there was multifocal necrosupurative meningoencephalitis associated with areas of malacia containing amoebic trophozoites. Immunohistochemistry of the brain was positive for N. fowleri. The disease should be included among the differential diagnosis of diseases of the central nervous system in cattle in areas where animals are exposed to hot, stagnant water.  相似文献   
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The growing contamination from the use of endocrine deregulator (EDs) has made the scientific community come worrying, because of this, studies to eliminate these pollutants in the water resources have intensified. Among the processes used, ‘Advanced Oxidative Processes’ (AOP’s) stands out, by means of heterogeneous photocatalysis for the removal of these organic pollutants present in the environment. The paper’s main point is on the synthesis of photocatalysts WO3-SBA-15 in the molar ratios Si/W (10, 25, 50, and 75) and the photocatalytic activity in the degradation process of 17α-ethynylstradiol (EE2), present in several water contaminants. The catalysts prepared were characterized by XRD, XRF, Raman, FTIR, UV-vis, adsorption, and desorption of nitrogen, and to determine the photocatalytic activity, frequency of turnover (TOF) was used. Through the characterizations, it can be observed that insertion of nanoparticles in WO3 did not cause changes in the mesoporous structure of the SBA-15 and there is presence of monoclinic, triclinic, and orthorhombic phases of WO3. The photocatalytic activity showed to be dependent on the calcination temperature and the molar ratio of the catalysts WO3-SBA-15, being the sample WO3-SBA-15(50) at 600 °C which presented the greatest degradation potential in the degradation of 17α-ethynylstradiol, with 98%, using ultraviolet radiation, for 4 h. Moreover, reuse of the catalyst did not show significant losses after 4 cycles, with 82% in EE2 degradation.  相似文献   
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Most drugs are synthesized by human medicine both for the treatment of men and animals and are also produced to maintain their physical and chemical properties for a time sufficient to serve a therapeutic purpose in treatments of some kind of illness. Ciprofloxacin is an antibiotic synthetically obtained in 1987 and belongs to the family of fluoroquinolones and is currently prescribed in certain treatments. This work was developed with the objective of evaluating the adsorption of the ciprofloxacin antibiotic in solution on zinc oxide (ZnO) supported on SBA-15-type mesoporous silica. The results showed that the post-synthesis method is effective in impregnating zinc oxide in SBA-15 and its structure has not been damaged and has not lost its organization in the hexagonal 2D planes. The ZnO-SBA-15 (10%) sample adsorbed 69.10% of ciprofloxacin (25 mg/L) in 180 min. Freundlich adsorption model was observed with the correlation factor of R2?=?0.9999, for the adsorbent ZnO-SBA-15 (10%), which showed the best sample. The kinetics was classified as pseudo-second order, as well as the thermodynamic parameters were determined, showing that the process has a spontaneous nature and a value of ΔH°?=?4.677 kJ/mol, evidencing that the process has the nature of physiosorption.  相似文献   
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Tropical Animal Health and Production - Subclinical hypocalcemia is a metabolic disorder characterised by a decrease in serum calcium (Ca) levels, with no clinical symptoms. The aim of this study...  相似文献   
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Antibiotics are a crucial line of defense against bacterial infections. Nevertheless, several antibiotics are natural products of microorganisms that have as yet poorly appreciated ecological roles in the wider environment. We isolated hundreds of soil bacteria with the capacity to grow on antibiotics as a sole carbon source. Of 18 antibiotics tested, representing eight major classes of natural and synthetic origin, 13 to 17 supported the growth of clonal bacteria from each of 11 diverse soils. Bacteria subsisting on antibiotics are surprisingly phylogenetically diverse, and many are closely related to human pathogens. Furthermore, each antibiotic-consuming isolate was resistant to multiple antibiotics at clinically relevant concentrations. This phenomenon suggests that this unappreciated reservoir of antibiotic-resistance determinants can contribute to the increasing levels of multiple antibiotic resistance in pathogenic bacteria.  相似文献   
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  1. Two migratory and endangered freshwater fish species, Salminus franciscanus and Brycon orthotaenia, are endemic to one of the most important basins for hydropower capacity in South America. These two fish are target species of conservation aquaculture programmes along the São Francisco River system.
  2. In order to implement effective strategies for the conservation of these species, microsatellite markers were developed and used to assess the genetic diversity and structure among wild groups. Fish were collected during the spawning season at four sampling sites, covering more than 1000 km.
  3. Polymorphism loci were assessed, and a total of 133 and 107 alleles were found for S. franciscanus and B. orthotaenia, respectively. Despite the critical conservation status, B. orthotaenia showed high levels of genetic diversity, comparable with those of other closely related species.
  4. Salminus franciscanus exhibited half of the genetic diversity of its sister species in terms of allelic diversity, indicating that this species will be more prone to genetic drift and inbreeding in conservation aquaculture programmes.
  5. The results of an analysis of molecular variance for microsatellite markers in these species (FST = 0.007 for S. franciscanus and FST = 0.003 for B. orthotaenia) and the estimated recent migration rates (>40% among sampling sites) support panmixia in both species, despite the heterogeneities of the riverscape.
  6. The results of this study and the microsatellites developed will play an important role in assisting agencies in making informed decisions on conservation aquaculture programmes.
  相似文献   
29.
This study aimed to evaluate the effect of the gradual replacement of fishmeal with fish protein hydrolysate (FPH) and biofloc flour (BF) in the diets of white shrimp Litopenaeus vannamei postlarvae (2 mg). Five diets (420 g kg?1 of crude protein) were formulated, and these replaced 0 (control), 10, 20, 30 and 40% (T0, T10, T20, T30 and T40, respectively) of the fishmeal. A commercial diet was used as an external control. The alternative ingredients FPH and BF were added at a ratio of 1 : 1. After 42 days, the shrimp survival was higher than 99% in all the treatment groups. A regression test indicated that the ideal fishmeal substitution level to obtain optimal zootechnical parameters (final weight, weight gain and protein efficiency) is between 15.16 and 16.5%. In this study, we demonstrated that BF and FPH are potential ingredients that can be used to replace fishmeal in L. vannamei postlarvae diets.  相似文献   
30.
The aim of this study was to verify the in vivo effectiveness of pumpkin seed (Curcubita pepo Linnaeus, 1753) in naturally infected ostriches in the Cariri zone, semiarid region of Paraíba State, Brazil. Forty-eight ostriches were used, African Black breed, of 14 to 36 months old, naturally infected by gastrointestinal nematodes. These animals were divided into four groups of 12 ostriches. Group 1 consists of animals treated with 0.5 g/kg live weight (l. w.) of pumpkin seed meal; group 2 received 1 g/kg l. w. of pumpkin seed meal; group 3 was treated with Albendazole 5 %, at the dosage of 1 mL/10 kg l. w.; and Group 4 was the control group and do not received treatment. Groups 1 and 2 received the treatment for three consecutive days, orally, at intervals of 7 days, totaling nine administrations. The Albendazole 5 % was administered one time, at the beginning of the experiment, according to the manufacturer’s recommendations. The groups treated with pumpkin seed showed a significant decrease in egg counts per gram of feces (EPG), wherein group 2 (1 g/kg l. w.) was the most effective. The control and drug groups showed no reduction in EPG. The results of the present study demonstrate that the administration of pumpkin seed was effective in controlling gastrointestinal helminths in naturally infected ostriches.  相似文献   
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